                                        :infl :present
                                        :sem {:tense :past}
                                        :subcat {:2 {:agr obj-agr}}}}))
-                   (unifyc h21
+                   (unify-check h21
                            {:rule "vp-future"
                             :synsem {:aux false
                                      :infl :future
                                      :cat :verb}})
-                   (unifyc h21
+                   (unify-check h21
                           {:rule "vp-imperfect"
                            :synsem {:aux false
                                     :infl :imperfect
                                     :cat :verb}})
-                   (unifyc h21
+                   (unify-check h21
                            root-is-head
                            {:rule "vp-present"
                             :head {:phrasal false}

                            :synsem {:aux false
                                     :cat :verb}})

                   (unifyc h10
                           {:head {:phrasal false
                                   :synsem {:cat :sent-modifier}}
                            :rule "s-modifier"})))

(defn aux-is-head-feature [phrase]
  (cond (= :verb (get-in phrase '(:synsem :cat)))
        (unifyc phrase
                (let [ref (atom :top)]
                  {:synsem {:aux ref}
                   :head {:synsem {:aux ref}}}))

                                     :cat :verb
                                     :sem {:aspect :progressive
                                           :tense :past}}})
                   (unify-check c10
                           root-is-head
                           {:rule "s-imperfect-nonphrasal-head"
                            :head {:phrasal false}
